Recent studies have demonstrated a marked interindividual variability of clopidogrel's capacity to inhibit platelet aggregation with a substantial proportion (11-34%) of the patients considered non-responders to clopidogrel treatment. Variable intestinal absorption is suggested to contribute to the inconsistencies in response to clopidogrel. However, little is known about intestinal absorption in subjects who had suffered from a stent thrombosis. The MAPCAT-study has been designed to investigate whether plasma pharmacokinetics (represented by Cmax, Tmax and the AUC) after a 600 mg loading dose are significantly different between subjects who have suffered a stent thrombosis and subjects who have not suffered a stent thrombosis.